Which expression is equivalent to 9 (15)?
O 9 (10+50)
O 9 (10+5)
O 9(1+5)
O 9 (1+50)

Trigonometry help asap

Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is